Air vaporizor

Abstract

A process for the use of ambient air as a heat exchange medium for vaporizing cryogenic fluids wherein the vaporized cryogenic gases are heated to a selected temperature for use or delivery to a pipeline.

1 . A method for vaporizing a a liquid natural gas, the method comprising: 
 a) passing the a liquid natural gas in heat exchange contact with air to vaporize the liquid a liquid natural gas and produce a vaporized gas; and,    b) heating the vaporized gas to a selected temperature by heat exchange with a heated liquid stream.    
   
   
       2 . (canceled)  
   
   
       3 . The method of  claim 1  wherein the heated liquid is an aqueous liquid.  
   
   
       4 . The method of  claim 3  wherein the heated liquid is heated by at least one of quenching heat exchange with a gas stream, heat exchange in a heat exchanger and heat exchange in a direct-fired heater.  
   
   
       5 . The method of  claim 4  wherein the gas stream is a waste heat stream.  
   
   
       6 . The method of  claim 4  wherein the gas stream is an exhaust gas stream from a turbine.  
   
   
       7 . The method of  claim 4  wherein the gas stream is heated in a direct-fired heater.  
   
   
       8 . The method of  claim 4  wherein the liquid is heated in a quenching heat exchange and in a heat exchanger.  
   
   
       9 . The method of  claim 1  wherein the selected temperature is a temperature suitable for delivery of the cryogenic gas to a user for use or delivery of the cryogenic gas.  
   
   
       10 . The method of  claim 9  wherein the user is a pipeline.  
   
   
       11 . A method for vaporizing a cryogenic liquid, the method comprising: 
 a) passing the cryogenic liquid in heat exchange contact with in a heat exchange zone having a top, bottom and middle portion to vaporize the cryogenic liquid to produce a gas;    b) heating the air passed in heat exchange with the cryogenic liquid by heat exchange with a heated liquid stream; and,    c) heating the cryogenic gas to a selected temperature by heat exchange with a heated liquid stream.    
   
   
       12 . The method of  claim 11  wherein the cryogenic liquid is liquefied natural gas.  
   
   
       13 . The method of  claim 11  wherein the heated liquid is an aqueous liquid  
   
   
       14 . The method of  claim 11  wherein the middle portion of the heat exchange zone is heated by heat exchange with the heated liquid.  
   
   
       15 . The method of  claim 11  wherein the heat exchange zone comprises a plurality of heat exchange vessels for passing air in heat exchange with a cryogenic fluid to produce a cryogenic liquid.  
   
   
       16 . A method for vaporizing a cryogenic liquid, the method comprising: 
 a) passing the cryogenic liquid in heat exchange contact with air in a heat exchange zone having a top, bottom and middle portion to vaporize the cryogenic liquid to produce a gas; and,    b) heating the air passed in heat exchange with the cryogenic liquid by heat exchange with a heated liquid stream.    
   
   
       17 . The method of  claim 15  wherein the cryogenic liquid is liquefied natural gas.  
   
   
       18 . The method of  claim 15  wherein the heated liquid is an aqueous liquid.  
   
   
       19 . The method of  claim 15  wherein the middle portion of the heat exchange zone is heated by heat exchange with the heated liquid.  
   
   
       20 . The method of  claim 15  wherein the heat exchange zone comprises a plurality of heat exchange vessels for passing air in heat exchange with a cryogenic fluid to produce a cryogenic liquid.  
   
   
       21 . A system for vaporizing a cryogenic liquid, the system comprising: 
 a) at least one heat exchanger having an air inlet, an air outlet, a cryogenic liquid inlet and a gas outlet and adapted to pass air in heat exchange contact with the cryogenic liquid to produce a gas; and,    b) a heater having a cryogenic gas inlet in fluid communication with the cryogenic gas outlet from the heat exchanger and a heated gas outlet.